XMPP4R-Simple makes XMPP in Ruby uhh... simple...

I thought it would be fun to build a control interface you could talk to over instant messaging – something like the IM bot that Twitter used to have.

I started by looking at XMPP4R, but a bit of reading led me to XMPP4R-Simple. Well, simple is always good. One gem install and 45 minutes later, I had a Ruby script that could log in to an XMPP server, listen to (and log) what people said, and respond with a simple message.

#!/usr/bin/env ruby

require 'rubygems'
require 'xmpp4r-simple'

logfile = File.join('..', 'log', "#{File.basename(__FILE__)}.log")
logger = Hodel3000CompliantLogger.new(logfile)

jabber = Jabber::Simple.new "username@domain.com", "password"
sleep 1
jabber.status(:away, "No one here but us mice.")
sleep 1

jabber.deliver("craig@xeriom.net", "I woke up at #{Time.now}.")

loop do
  begin
    jabber.received_messages do |msg|
      jid = msg.from.strip.to_s
      logger.info "%s said: %s" % [ jid, msg.body ]
      jabber.add(jid) if !jabber.subscribed_to?(jid)
      jabber.deliver(jid, "Nom nom nom.")
    end

    jabber.presence_updates do |update|
      jid, status, message = *update
      logger.info "#{jid} is #{status} (#{message})"
    end

    jabber.new_subscriptions do |friend, presence|
      logger.info "#{friend.jid} #{presence.type}"
      jabber.add(friend.jid) if !jabber.subscribed_to?(friend.jid)
    end
  rescue Exception => e
    logger.error e.to_s
  end
  sleep 1
end

The loop does three things: it handles incoming messages (logging them and replying with a deeply intellectual “Nom nom nom”), tracks presence updates, and auto-accepts new subscriptions. The sleep 1 calls keep us from hammering the server.

Our own little pet XMPP client. How cute is that?

If you’ve found this article useful, I’d appreciate a recommendation at Working With Rails.